An artist's concept depicts how DARPA's SeeMe program would work. The program aims to design disposable satellite clusters that will give soldiers location-based information in places where they would typically not have satellite coverage. (Source: DARPA)

Beth, it's a very real problem. In the last years of operation the space shuttles suffered several impacts. They've had several windows pitted with paint chips, and a radiator took a pretty substantial hit.

The final stage of satellite boosters often goes into orbit. Those that are liquid-fueled, if simply abandoned, have been known to explode from the residual fuel and oxidizer. The resultant debris cloud is much worse than just an empty stage. Most launch companies now provide a means of venting the fuel after releasing the payload to prevent this sort of occurrance.

In 2009, a first-of-its-kind collision occurred between two whole satellites. An Iridium communications satellite was nailed by a Russian Cosmos satellite. The velocities involved are measured in kilometers per SECOND.

@Mydesign, one of the reaons you have not seen satellites that are inexpensive and simple is the economics of launch. This has been something that the military has been working on for a long time. So, while it is not a big deal to design the satellite to a price, it is the inexpensive (and on-demand) launch capability that is the issue.

My father worked on a program, in last century of the last millenium, that attempted to build a launch system for such satellites utilizing a super gun. These are very large cannon. The idea was originally developed by the Germans in WWII, I believe. That concept relied on being close to the equator. Some of his colleagues got to spend several months on a Caribean island.

The price point on these "disposal" satellites is intriguing. I'm wondering specifically is there are any guidelines or requirements in the specification for these units that denote material choices or design approaches that would push the price of these units down so significantly. Seems like a pretty big jump.

@mydesign: Are you saying there is so-called junk or garbage littering the new frontier of space before any human population gets its hands on it in terms of day to day living? That's a pretty scary thought.

Elizebeth, now a days the junk items and garbage's are causing many issues for space stations and satellites. Sometimes collisions are happening between these garbages with space vehicles and satellites causing damages to the satellites. So scientists are planning for a mechanism to clean up the space junk items for smooth navigation of space vehicles and satellites.

Elizabeth, finally satellites are also coming to use and throw way. I think the GPRS services are providing through a consortium of different satellites at different orbits, so for GPRS navigation, the range or line-of-sight may not be a problem. But if GPRS technology is using for military purpose, security and privacy may be an issue. There are also other options like networking of satellites for communication and geo tagging etc are feasible mechanisms with the country.

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